1. Field of the Invention
The present application relates to coupling assemblies for interconnecting confronting ends of a pair of fluid conveying members, and more particularly, to a clamshell variety coupling assembly for interconnecting confronting ends of a pair of fluid conveying members.
2. Description of the Related Art
There are a number of prior art couplings that are used for interconnecting various types of fluid conveying lines or conduits. Depending upon the type of fluid to be conveyed, the prior art couplings may be designed to handle special safety requirements. Particularly for conduits which convey fuel, there is always a concern for designing a coupling so that an electrostatic charge does not build up on one of the coupled sections of the line. A stored electrostatic charge may give rise to the hazard of an electrical spark in the presence of vaporized fuel. Discharge of the spark by grounding or by flexing of the coupling in such a manner to bring electrically bonded parts of the coupling out of contact with one another may cause instantaneous combustion of any vaporized fuel which in turn can cause ignition of the fuel conveyed in the lines. Buildup of an electrostatic charge by ionization of fuel as it is conveyed through the fuel lines can be referred to as a static buildup of an electric charge. Lightning strikes can also create a spark and such strikes are commonly referred to as dynamic causes for creating an electrical charge. Thus, a coupling should also have the capability to dissipate a dynamic electrical charge, such as one caused by a lightning strike. Particularly for lightning strikes, it is important that the coupling have the capability to quickly dissipate the electrical charge due to the potential magnitude of a spark caused by the lightning strike.
Despite the advances in coupling designs, most fluid conveying lines still utilize metallic flanges which are sealed to the coupling by deformable o-rings. These type of sealing rings may electrically insulate the coupled sections of the line from each other, thus any ionization of fuel that flows through the lines may give rise to a differential electrostatic charge between the coupled sections, which creates a spark gap. Accordingly, there is still a need to ensure electrical conductivity across the coupled sections of the fuel lines to prevent electrostatic buildup to reduce the complexity, cost, and size of the coupling as well as improve overall performance.